As a standard system of television, so-called “NTSC (National Television System Committee) system” (hereinafter referred to as “NTSC system”) is employed in Japan and other countries. The SMPTE standard 170M and 259M define this system.
On the other hand, nowadays, the High Definition Television Systems (hereinafter referred to as “HDTV system”) is also employed and used for part of television broadcast. The SMPTE standard 292M, 260M and 274M define this system.
Therefore, picture signals stored on a magnetic medium (e.g. a videotape for a broadcasting station) for recording picture and voice data on a broadcast from a television broadcasting station have various formats so as to be adapted to the above-mentioned systems. Among these formats is a picture signal format corresponding to the NTSC system defined by the SMPTE 170M.
Picture signals of the NTSC system are generally fed into a dedicated apparatus capable of outputting picture signals of the NTSC system for display. Similarly, picture signals of the HDTV system are generally fed into a dedicated apparatus capable of outputting picture signals of the HDTV system for display. Therefore, when picture signals of the HDTV system are fed into a dedicated apparatus capable of outputting picture signals of the NTSC system for display, the picture signals of the HDTV system are converted into those of the NTSC system by a down converter and fed into a dedicated apparatus capable of outputting picture signals of the NTSC system for display.
To the contrary, when picture signals of the NTSC system are fed into a dedicated apparatus capable of outputting picture signals of the HDTV system for display, the picture signals of the NTSC system are converted into those of the HDTV system by an up converter and fed into a dedicated apparatus capable of outputting picture signals of the HDTV system for display.